Two common nonsynonymous paraoxonase 1 (PON1) gene polymorphisms and brain astrocytoma and meningioma

<p>Abstract</p> <p>Background</p> <p>Human serum paraoxonase 1 (PON1) plays a major role in the metabolism of several organophosphorus compounds. The enzyme is encoded by the polymorphic gene <it>PON1</it>, located on chromosome 7q21.3. Aiming to identify genetic variations related to the risk of developing brain tumors, we investigated the putative association between common nonsynonymous <it>PON1 </it>polymorphisms and the risk of developing astrocytoma and meningioma.</p> <p>Methods</p> <p>Seventy one consecutive patients with brain tumors (43 with astrocytoma grade II/III and 28 with meningioma) with ages ranging 21 to 76 years, and 220 healthy controls subjects were analyzed for the frequency of the nonsynonymous <it>PON1 </it>genotypes L55M rs854560 and Q192R rs662. All participants were adult Caucasian individuals recruited in the central area of Spain.</p> <p>Results</p> <p>The frequencies of the <it>PON1 </it>genotypes and allelic variants of the polymorphisms <it>PON1 </it>L55M and <it>PON1 </it>Q192R did not differ significantly between patients with astrocytoma and meningioma and controls. The minor allele frequencies were as follows: <it>PON1 </it>55L, 0.398, 0.328 and 0.286 for patients with astrocytoma, meningioma and control individuals, respectively; <it>PON1 </it>192R, 0.341, 0.362 and 0.302 for patients with astrocytoma, meningioma and control individuals, respectively. Correction for age, gender, or education, made no difference in odds ratios and the <it>p </it>values remained non-significant. Haplotype association analyses did not identify any significant association with the risk of developing astrocytoma or meningioma.</p> <p>Conclusions</p> <p>Common nonsynonymous <it>PON1 </it>polymorphisms are not related with the risk of developing astrocytoma and meningioma.</p

CaZF, a Plant Transcription Factor Functions through and Parallel to HOG and Calcineurin Pathways in Saccharomyces cerevisiae to Provide Osmotolerance

Salt-sensitive yeast mutants were deployed to characterize a gene encoding a C2H2 zinc finger protein (CaZF) that is differentially expressed in a drought-tolerant variety of chickpea (Cicer arietinum) and provides salinity-tolerance in transgenic tobacco. In Saccharomyces cerevisiae most of the cellular responses to hyper-osmotic stress is regulated by two interconnected pathways involving high osmolarity glycerol mitogen-activated protein kinase (Hog1p) and Calcineurin (CAN), a Ca2+/calmodulin-regulated protein phosphatase 2B. In this study, we report that heterologous expression of CaZF provides osmotolerance in S. cerevisiae through Hog1p and Calcineurin dependent as well as independent pathways. CaZF partially suppresses salt-hypersensitive phenotypes of hog1, can and hog1can mutants and in conjunction, stimulates HOG and CAN pathway genes with subsequent accumulation of glycerol in absence of Hog1p and CAN. CaZF directly binds to stress response element (STRE) to activate STRE-containing promoter in yeast. Transactivation and salt tolerance assays of CaZF deletion mutants showed that other than the transactivation domain a C-terminal domain composed of acidic and basic amino acids is also required for its function. Altogether, results from this study suggests that CaZF is a potential plant salt-tolerance determinant and also provide evidence that in budding yeast expression of HOG and CAN pathway genes can be stimulated in absence of their regulatory enzymes to provide osmotolerance

Potassium and Sodium Transport in Yeast

[EN] As the proper maintenance of intracellular potassium and sodium concentrations is vital for cell growth, all living organisms have developed a cohort of strategies to maintain proper monovalent cation homeostasis. In the model yeast Saccharomyces cerevisiae, potassium is accumulated to relatively high concentrations and is required for many aspects of cellular function, whereas high intracellular sodium/potassium ratios are detrimental to cell growth and survival. The fact that S. cerevisiae cells can grow in the presence of a broad range of concentrations of external potassium (10 M–2.5 M) and sodium (up to 1.5 M) indicates the existence of robust mechanisms that have evolved to maintain intracellular concentrations of these cations within appropriate limits. In this review, current knowledge regarding potassium and sodium transporters and their regulation will be summarized. 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Yellow phosphors doping with Gd3+ , Tb3+ and Lu3+ in MTiO3 (M = Mg and Sr) luminescence properties

This paper reports Gd3 + , Tb3 + and Lu3 + doped MTiO3 (M = Mg and Sr)-based phosphors which were synthesized by the conventional solid-state reaction method, their crystal structures and luminescence properties were investigated. X-ray diffraction patterns (XRD) showed that phosphors sintered at 1000 A degrees C for 2 h were the pure SrTiO3 and MgTiO3 phases. The optimization of reaction conditions was carried out by thermogravimetry and differential thermal analysis (DTA/TG) methods. Surface and elemental analyses were performed by using SEM instrument. The excitation and emission spectra were recorded by a photoluminescence spectrophotometer (PL). The thermoluminescence (TL) properties of MgTiO3:RE (RE = Gd3 + , Tb3 + , Lu3 + ) and SrTiO3:RE (RE = Gd3 + , Tb3 + , Lu3 + ) were investigated

Luminescence of a Novel Near-UV Emitting Phosphor BaB8O13:Pb2+

Ba1-x Pb (x) B8O13 (0.005 a parts per thousand currency signaEuro parts per thousand x a parts per thousand currency signaEuro parts per thousand 0.0175) phosphors were synthesized by a conventional solid-state reaction using BaCO3 (99.99\%), H3BO3 (99.80\%), and PbO (99.99\%) as starting materials. X-ray powder diffraction (XRD) analysis confirmed the formation of BaB8O13. Measurement of the photoluminescence (PL) excitation spectrum of BaB8O13:Pb2+ shows this phosphor can be efficiently excited by ultraviolet (UV) light from 200 to 280 nm and presents a dominant luminescence band centered at 360 nm. The effects of the doped-Pb2+ concentration in BaB8O13:Pb2+ on the PL were investigated in detail. The results showed that the relative PL intensity increased with increase in Pb2+-concentration reaching until 0.01 mol, where the intensity maximum was reached, and then it decreased due to concentration quenching. The thermoluminescence (TL) properties of BaB8O13 samples with different concentration of Pb2+ were also investigated

Thermoluminescence Kinetic Parameters of TLD-600 and TLD-700 after Cf-252 Neutron+Gamma and Sr-90-Y-90 Beta Radiations

The thermoluminescent (TL) properties such as glow curve structure, relative thermoluminescence sensitivity, dose response linearity of lithium fluoride thermoluminescent dosimeters (LiF)-Li-6: Ti, Mg (TLD-600) and (7) LiF: Ti, Mg (TLD-700) are investigated after irradiation Cf-252 neutron+gamma and Sr-90-Y-90 beta sources at room temperature and then the obtained results are compared. The kinetic parameters, namely the order of kinetics b, activation energy E-a a and the frequency factor s, are calculated using the computerized glow curve deconvolution (CGCD) program. The effect of heating rate on the glow curves of dosimeters is also investigated. The maximum TL peak intensities and the total area under the glow curves decrease with the increasing heating rate. There is no agreement with the kinetic parameters calculated by the CGCD program for both radiation sources

The analysis of thermoluminescent glow peaks of natural zircon after ß-irradiation

The additive dose (AD), Tm(Ea)-Tstop, repeated initial rise (RIR), peak shape (PS) and computerized glow curve deconvolution (CGCD) methods were used to analyze the thermoluminescence (TL) glow peaks in natural zircon after ß-irradiation between the dose level 0.015 Gy and ? 10 kGy. The CGCD and Ea-Tstop methods indicate that the glow curve of this material is the superposition of at least seven glow peaks, which were referred to as P1-P7, in the temperature range between room temperature (RT) and 400 °C. The dose responses and fading process of individual TL peaks of this material were also examined. The dose response behaviors of all peaks are different from each other and they are saturated at different dose levels. Peaks 1 and 2 completely disappeared after 1 month storage in the dark room at RT. On the other hand, the intensity of peaks 3 + 4 was approximately reduced to 80% of its original value whereas the other peaks (P5-P7) were not sufficiently affected during this period. © 2006 Elsevier B.V. All rights reserved.This work has been supported in part by Mersin University under contract no. BA FBE. FB(SG) 2005-1TL. The authors are also grateful for the financial supports from the Research Fund of Gaziantep University and TUBITAK

Neutron plus Gamma response of undoped and Dy doped MgB4O7 thermoluminescence dosimeter

WOS: 000470046200014PubMed ID: 30825838Thermoluminescence properties of undoped and Dy doped MgB4O7 compounds were studied with the irradiation of Cf-252 source. The TL kinetic parameters of MgB4O7: Dy were studied by computer glow curve deconvolution (CGCD) method. The glow curve structures of 1% Dy doped magnesium tetraborate compound consists of at least five glow peaks with a main dosimetric peak at about 220 degrees C. The highest sensitivity which is approximately 1.90 and 1.47 times higher than that of TLD-600 and TLD-700 was found for MgB4O7: Dy (1 mol%). The results clearly showed that Dysprosium doped magnesium borate has a potential to be considered as the thermoluminescence neutron + gamma dosimeter.TUBITAKTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [115F268]This work was supported by TUBITAK, the project number is 115F268